Multistage centrifugal blower



T. W. GREEN. MULTISTAGE CENTRIFUGAL BLOWER.

APPUCATION FILED MIG.9, i918. 1,350,724. PtentedAug. 24,1920.

3 SHEES-SHLE] l. www 7 FIG- 1 "Z 46 t Y ...WW IWENTOR GREEN MUL'USTAGE CENTRIFUGAL BLOWER.

APPLlcMmN m50 AuG.9.191B. 1,350,724, Patented Aug. 24, 1920.

3 SMBus-SHEET 2.

INVENTOR ATTORHEY T. w. GHLEN. MULTISTAGE CENTRIFUGM. BLOWER.

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THOMAS W. GREEN, 0F TRENTON, NEW JERSEY.

MULTISTAGE CENTRIFUGAL BLOWER.

Application filed August 9. 1918,

Be it known that l, 'l`nou.\s W. (iiuznN, a citizen ol the United Htates.' residing at 21 Bellevue avenue, Trenton, in the eounty of Mercer and State ot' New Jersey, have invented a eertain new and useful Multistage Centrifugal lower, of which the following is a specification.'

My invention relates to centrifugal pumps, blowers or exhausters for air, gas and other fluids intended to inerease the pressure hy sueeessive eoinpressions in different stages or compartments through whieh the, luid passes in series.

My main purpose is to increase the area of the ports by whieh the fluid passes into the compartments.

A 'further purpose. is to provide a plurality of vanes in the rotor for eaeh inlet port in the stator.

A further purpose is to use inlet ports having eireumferentiul widths considerably in` exeess of the distance between adjoining vane edges.

A further purpose is to supply end inlets for one or more olf the sets of vanes used.

A further purpose is to stage axially as well as radially.

A further purpose is to stitl'en the vanes.

A further purpose is to adapt the eonstruction tothe use ot' east forms and rolled or pressed sheet metal eouneetious.

My invention relates hoth to the proeesses involved and to apparatus by whiieh the proces-ws may be rarried out.

Further purposes will appear in the speeiieation and in the. Claims.

I have preferred to illustrate my invention by hut two l'ornis thereof, seleeting fornlswhieh are praetieal, eflieieut and thoroughly reliable and whieh at the same time well illustrate the prineiples ol my invention.

Figure 1 is a longitudinal seetion corresponding to line l--l of Fig. 5 ot' a preferred form ot' my invention;

Fig, Qisa fragmentary seetion upon line 2--2 oi,I"ig. l,

Figs. 3 and l are lnrspeetivey views of differing 'Forms of vane whieh may he used in my invention.

Fig. ."i is a sei-tion Fie. 1.

"ig (i is a fragmentary seetion `showin r a portion of Fig. with the parts in differupon line 5 5 of ent relative positions.

Specification of Letters Patent.

Patented Aug. 24, 1920.

Serial No. 249,079.

Fig. 7 is a top plan view ol'l one ol the rylindrieal partitions of the stator.

Fig. H is a seetion upon line H-H ol' Fig, 9 'showing a modified form. 4

Fig. 5J is a section upon line. 0 1) ot' Fig. 8.

Fig. 1i) is a fragmentary sei-tion eorresponding generally to Fig. l), hut showing a dillerent eonstruel ion ol' vane.

Fig. l1 is a seetion (corresponding generally to Fig. H, hut showing a single stage nieehunism whieh may be multistaged on the opposite side, it desired.

ln the drawings similar numerals indieate roi-responding parts.

ll'hough I reeognize that my invention is applirahle to various pumping. blowing and exhausting uses in the handling of air. gas, water and many other lnids` both gaseous and 'luid. and intend to eover sui-h varied applieations herein, it is ineonvenient to make the referenees to the l'unetiou and the fluid general where they oeeur, and I will therefore, as a matter ol' eonvenienee` ile serihe the invention in terms of air blowers, hut without intention to limit the invention thereto.

In the operation ol multistage blowers the total eapaeity has been limited by restrielion ol' the size of the ports through the l'ixed eylindrieal partitions ol the stator, and the partitions themselves have heen unduly limited hy struetural eonditions redueing the extent olI lluid llow and the eapaeities oi' the individual eompartnlents handling the air.

l have undertaken to improve the inlet openings both by end inlets and hy ilu-reasing the nlunher ot vanes (and roi-respondingly the numlier of poeketsI or compartments) per inlet opening, with a view to permitting larger radiaily-extending ports and better sealing funi-tions. l have also provided for a larger Ilse oll pressed or rolled metal. permitting the more general use ol' this thinue and4 lighter metal. instead ofthe east metal Vfrom whieh the eouslruetion would otherwise he Iliade.

t`onsidering `lirsl the l'orln in Figs. is?. and viewing it as an illustration merely the outer easing or trame is made up of two spaeed ends l5, 1G united by a nearly eylindrieal eentral einer IT. The easing may he divided in any way whieh eonvenienee suggests to l'aeilitate quick assemblage oly the meehanism.

The rotor is mounted upon a shaft IIR which is supported in any suitable bearings and which carries a hub 19 and spider 20.

The venes are mounted on o posite sides of the spider in circumferentia ly arranged sets or groups and are spaced from each other by the cylindrical, lnwardly-directed partitions of the stator.

In Fi 1 four sets of vanes are shown on each sidi, indicated at 21, 22, 23 and. 24 on the one side; and 25, 26, 27 and 28 on the other side,

Their preferred angles with the radii of the rotor are seen in Figs. 5, G, 8 and 1l.

Between these sets of vanes the cylindrical partitions from the stator project from 0pposite sides at 29, 30 and 31 from the one end and 32, 33 and 34 from the other end with continuous stator partitions from end to end at 35. A

The inner vanes 21 and 25 are merely angularly placed blower blades which are Secured upon dia onal faces 3G of the hub and perform no ot 1er function than to sweep the air through the ports 37 of the partitions 29 or 32, so that it may successively be forced through any desired number of ports 38, 39 and 4() of partitions or cylinders of successively increasing diameter.

The vanes 22 and 26 are of the type shown in Fig. 3, comprisin bodies 41, extending at an angle to the refills as seen in such iigures as 5 and G, and circumferentially-extending ends 42 and 43, the ends 42 being shortened to provide for admission of air at the ends i. e., between them and the center. The ends 42 of adjoining vanes arc secured in such manner as to overlap, each one suporting the adjoining one, as best seen in ig. 2, while the ends 43 are separately secured to the spider to hold the entire vane. 1n this manner thc venes and their ends form the sides and ends of boxes which are Without. either tops or bottoms and which are completed by the cylindrical Fixed partitions 29, 30 and 32, 33.

In the case of the outer sets of vanes, inlet of air at the end is not intended4 and the ends are full, as seen at 44 in Fig. 4, correspending to the form of vane having body 41', seen at 23, 24, 27 and 28. These also overlap at their outer ends, farthest from the spider, as seen in Fi 1, and are united separately to the spider gy any suitable fastenings at their inner ends.

This forms a convenient and desirable -method of support of venes t'o permit the use of pressed metal and alords a maximum of stiflening.

I show a desirable form of mounting,r for the stator partitions 2' -35, forming circu lar axially-extending hanges upon the end pieces, or rigidly supported with respect to them, and fastening the partitions to these flanges at intervals. The fianges thus lcontinuously support the partitions upon either the inner or outer side (radially) thereof and may be secured to them at any desired intervals to stifen them, permitting the use f of cylindrically bent thin sheet metal for this purpose.

The outer partitions 31, 34 and 35 are shown as supported by flanges 45, 40, 45', 46', integral with the casing and by common fastening means which can be passed conveniently throu h both. The partitions 30 and 33 engage an es 47, 47', also integral with the casings. or convenience in manu facture and assemblage the supportingr structure radially inside of this point is sep arated from the rest of the heads and is fastened to the same flanges but upon opposite sides of the partitions. The inner supporting structure comprises outer fianges 48, 48', inwardly extending web ends 49, 49 and rin s 50, 50. The lian es 48, 48 are bolted to anges 47, 47. lVit 1in the ends, I form a series of ports 51, 51 and the rings are used `for the support of the partitions 29 and 32. i

The air passes into the casings at both ends through openings 52, 52', into spaces 53, 53 from which it distributes through the center along the shaft to the ports 37. These ports and ports 51 open into compartments of the same set and, being placed in approximately the same planes, considered with respect to the changing angular posi tions occupied by the compartments, fill the same compartments concurrently or nearly so. There is one difference; that the air is driven through the ports 37 by reason of the belt or motor-driven rotor 4through vanes 21 or 25, whereas the air flows freely through ports 51, 51.

This gives a very large volume of air inlet into the particular compartments 54 which are opposite the ports at the time, with successive movements of the air into compartments 55 and 56, as the rotor turns.

he air is successively driven through ports 38, 39 and 4() and finally emerges rinto an outer circumferentiallyextending compartment 57 by which it is conducted to the air receiver or storage thrpugh one or more openings 58.

One of the features of my invention is to provide an extent of opening into the compartments, measured in a circumferential direction, considerably in excess 4of the thickness of the adjoining inner and outer venes so that these vanes will not close the openings (ports) at any time during their passage across the openings. This is made possible by the relatively large numberof venes which I supply per port, s'o that there are a plurality, preferably two or more 'compartments closed on the inside at one time, while a third compartment is being filled .from the interior through a large port opening. v

Likewise preferably two or more adjoining compartment.` are closed on the outside while the intervening compartments tween these successive sets of two or more closed compartments) are discharging through large ports intov outside compartment. llcre again the port is preferably much wider. circlnn't'erentially than the outer and inner surfaces (thickness) ot' the vanes which wall the compartments, so that the ports are never fully closed by either the outer or inner adjoining vane surfaces. '.l`he combination between the multiplicity ot' c( mpartments and the wide opening makes the wide opening ot the ports and the endopening ports permissible and effective.

ln the position shown in Fig. 5, the rotor is moving in counter clockwise direction. r1`he compartments 54 have been receiving air from the interior space about the hub and end ports 5l and are soon to be cut ott', whereas the compartments 542 are just beginning to receive air through the ports and the end ports. At the same time the compartments 5l" are expelling air through the ports 3H into compartments 55', -other similar compartments 55: are sealed both inside and outside and compartments 55" are expelling air to compartments 5b through ports Il!) and still other compartments 554 have just expelled their air. ('ompartments 56" are expelling air tinally into the space 5T through ports lll and the other compartments ol' this set are either approaching the discharge point or have discharged.

The section shown in Fig. shows a slightly advanced position which the rotor assumes with rcspectto the ports and in which the compartment 5l is now receiving air to its tallest extent t rough the ports 3T and 5l. the ports 54* are discharging into compartments 55' and compartments 5G are discharging air through yorts 4U.

'l`liongh the end ports 5l do not have the pressure olI diagonal blades 2l and 25, to 'torce the air through them into the oompartments and for this reason are not quito as ellective t'or thei area ot" surface as the ports IIT in lilling the compartments 54, they open into the inner part ot' the compart ments (the part of smallest diameter) and provide considerable llow dueto suction because oll the slope oll the vanes.

'l`he ports which are considered radial, to distinguish lroni the end ports. are prei'- erabl'v at an angle to the radii.

ln the lorm .shown in Figs. H lll the same general a rrangenn'nt ol' successively increas ing .stages ol' v\ ancs is used, but the two sides have separate outlets instead ol litting into a common oulet. 'llie outlet l'roni one side supplies the inlet air to the other` thus iucreasing the compression ol' a smaller volume ol` air. There are also some dillerences in the points at which the air is received and discl'iarged from the casing, in the manner in which the vanes are supported, and in the vanes themselves.

The air inlet 522 is at the top and the air at atmospheric pressure enters the space about the shaft at one end only, passing through the successive radial and Yend ports into comlmrtments corresponding with those in Figs. 1 and 5. The partitions 29', 3U', 31' and 35 are secured directly to flanges upon the inside of the easing and the vanes are open-ended, sealing on the inside against strips 5S), 52)', 592.

The air is expelled from the stages at the left end ot' the figure into an outer com partment 57 from which it passes through a passage (il), to an inlet 52"* at the right hand side ot' the ligure and begins a series of further compressions here, in successive stages from the inside outwardly. There are but two series of compartments at the right haml side in the illustration, on account of the smaller diameter remaining inside the passage (it). These two compartments are constructed in the same general manner as those upon the left and discharge into an outer channel 572 whence the air vis passed out through a discharge opening 58.

In Fig. l1 a single stage type is shown, such as might be used separately for special purposes or, in a smaller construction, as one stage ot a multi-stage blower of the general character shown in Fig. t). This shows the adaptability of a construction of the general character of Fig. 9, to use with ports in the ends ot' the compartments through the stator.

ln these later forms as in the form shown in Figs. 143, the air passes into the first set ot' compartments through wide ports and is relatively compressed in that compartment with respect to the entering air by reason of the angular position of the vanes forming the compartment. 'ith progress of the rotor the inner ends of the successive compartments are closed before the outer ends of thecompartments come in line with the discharge openings. 'l'his gives an effective seal, preventing leakage ol the air inwardly. Where there are outside sets of compartnn'nts the air l'rom the inner compartments, sealed as described, is forced into the outer set through large ports open ing when the compartments have been moved l'orward into line with the ports and the operation is repeated. From the outside set of compartments the air is discharged into the passage. 57, 5T', or 3T by which it is led ont to the receiver or to another series ol'compartments l'or l'urther compression as preferred.

lt. will be obvious that my invention may be applied to a great variety of other strut tures and with other means while still seeuringat least a. part of the benefits of the combinations and structure invented by me.y

Haring thus described my invention,wl1at I claim as new and desire to secure by Let ters latent is:

1. ln a eentrit'ugal fluid pump, a` pair ot coaxial, eylindriral iixed partitions of dit'- ferent diameter havingr ports out ot' line radially, in eomhination with a rotor having vanes at an angle to the radii, the inner and outer surfaces of the vanes, considered radially, heilig:` ot' smaller eireumt'erential extent than the ports so that they are ineapahle of eoverinpr the edges ot' adjoining;r port openings and bearings for the rotor.

2. In a eentril'ugal iuid pump, a stator haviul;r eoaxial eylindrieal partitions oi diti'erent diameter and end walls therefor, the, partitions being ported ont ot line radially inthe two partitions, in eomhination with a rotor, bearings therefor, a plurality of vanes at an angle to the radii earried hy the rotor and extending eireuniterentially at their outer and inner limits less than the ril-eumferential extent ot' the ports respeetively and vanes earried by the rotor tending' to torre the air through the inner ports.

3. In a fluid pump, a stator, a pair of eoaxial. eylindrifal partitions therefor having ports out. ot' line radially and an end wal! having ports approximately eiirrespomlinnr in angular position with the ports in the inner partitions, in eonihination with a rotor, hearings therefor, vanes upon the rotor at an angle to the radius fitting between the partitions and havin;r less eireuuiferential extent at the inner and outer edges than the ports in the adjoining partitions.

4. In a fluid puinp, a stator, a pair ot' eoaxial, eylindrieal partitions tlierei'or havin,"r ports out oi line radiaily, an end wall having ports in angular position approxiniatelyr eorrespoinling with the ports in the inner partitions, in eon'ihination with a rotor, vanes upon the rotor at an angle to the radins Iittinar between the partitions and having less eireunifeiential extent at the inner and outer edges than the ports in the adjoiningr partitions and means rarried hy the rotor for fori-ing: air through the inner partitions.

In a iluiel pump, a stator, a pair of eoaxial, eylinilrieal partitions earried thereby, the outer partition being ported, an end wall at one end ol' the spare between the partitions, ports at intervals in the end wall. a rotor, hearings tlierel'or and vanes rarried by the rotor between the two partitions,

(i. ln a (luid pump` a stator, a pair of ew axial, eylindrieal partitions earried thereby, the outer partition heineported, an end wall at one end ol the spare between the partitionsports at intervals iu the end wali, a` rotor, hearings therefor, and vanes earried bv'tlie rotor between the two partitions and having circumferential extent at the end less than the port in the end Wall.

7. 1n a multistage fluid pump, a stator, an outer easing therefor, a plurality of coaxial, eylindrieai spared partitions having ports out of line radially, in adjoining partitions and end walls between the partitions, in eomhination with a rotor, bearings therefor and vanes carried by the rotor lying between the successive pairs of partitions and having less eireuniterential extent at the inner and outer edges than the ports in the adjoining partitions.

8. In a tlnid pump7 a stator, a pair ol eoaxial, evlindrieal partitions attached thereto, ported out ot' line radially, in combination with a rotor, bearings therefor and vanes rarried hy the rotor in number exeeeding twiee the number of ports in the partitions and having less eireuint'erential extent at the inner and outer edges than the ports in the adjoining partitions.

l). ln a multistage fluid pump, a stator, a pluralityv of eoaxial eylindrieal partitions earried thereby having ports out of lino in adioininrr partitions radiaily and end walis i'or theI spaees hetween the partitions, the end wallsl hetween the iunerniost pair of' partitionsl being ported and those between partitions farther out from the axis` heini;r without ports.

Ui. A multistage lluid pump comprising;r two sets ot' eoaxial eylindrieal fixed partitions havinir ports out ot' line radially heiueen adjoiningr partitions and oe-eupyinpr a` small part only of the eireumierein'e, a rotor lying between the two sets. hearings for the rotor. oppositely direeted vanes on the rotor lyingga between the partitions and having,r eireuint'erential extent less than the ports in the adjoiningr partitions; in ronihination with walls direeting the diseharge from one set of partitions and vanes into the inner Spaees of the other set ot partitions. and vanes.

l1. ln a multistage fluid pump, a stator harinar a Series ot coaxial, eylindrieal partitions ported at intervals, the ports in ad joiningr partitions heinrer out ol line radially, in eolnhination with a rotor having: a lSeries ot sets of vanes, one set between each adjoiniiu r two partitions and exceeding in number twice the number of the ports, the eireumterential extents of the inner and outer effet-tive vane edges. rrossing the ports hein; Ir less than the eirelunterential extent of the ports in the adjoining;r partitions so that the ports are never elosed.

l2. ln a multi-stage fluid pump, a stator eoin|n'isiner ends and a rentral easirugr Seetion unitini,r the ends. a rotor havin;1r hearing in the stator, a spider on the rotor and a plurality oi hlades mounted upon the spider, a plurality' of eoaxial, eyliiulrieal partitions supported h v the stator and having` ports therelhrimgjh at inter fals, the ports of ad- 4 titions littin thelanges and Asecured therel joining partitions being radially out oflline, a series of blades supported upon the rotor between each pair of artitionsand in number` more than twice t e number of the portsy in the adjoinin partitions and end ports in the end wal s for one of the series of vanes. v l i 13. In a multistage fluid pump, a stator having an end wall, interior circular flanges thereon and separate, spaced, cylindrical.,

partitions Vrigidly secured t0 said flanges.

14 In a multlstage fluid` ump, a stator com irisin opposite end wa'ls and having.

inwL rdlyirected coaxial cylindrical flanges thereon, in combination `with separate, spaced, inwardly' directed partitions fitting the flanges and secured thereto. i

15. In a multistage fluid ump, a stator comprising opposite end wa ls andaxially directed, coaxial, cylindrical flanges thereon in combination with inwardly directed parto, one of t e partitions extending across from a flange on one end to a flange on the other end.

16. In a multistage fluid pump, a stator having circumferentially-extending, axiallyf directed flanges in combination with separate, spaced, cylindrical partitions secured thereto and an end wall secured to one of.

the flanges.

. 17. In a rotary fluid pump, a rotor spider A in combination with vanes carried thereby,

flanges on the vanes at their inner ends secured to the spider and flanges onthe outer ends of the vanes oyerlapping to .stillen one vane by securing it to t e next adjoining vane.

18. In a rotar lluid pum arotor vane com risin a b ade adapte 4.to lie at an ang e to t e radius and 'oppositely-directed flan es for attachment respectively to a 4'rotor spicer and to the next adjoining vane.

19. VIn a rotary fluid pump,a -rotor vane comprising a blade and o positely-'directed' flanges, one flange ada te to be attached to the rotor and the ot erV of partial -axial length adapted to engage the next vane and relieved to fpermit air inlet through the end inside the ange. y 20. A rotor, a vane having a lian e for attachment thereto and al ila e at t e o posits end thereof occupying ess than t entire radial extent of the vane, in combination with a stator adptedto permit air in'- let op ite this last ange. f 21. n'a rota iluidpump, a stator having an axiallyfdi an end wallsecured to said flange and haw ing endv ports 4therein and an axially exfaces of a common support,

rected cylindrical :lange,

tending flange about the ports in combina- 'tion with a rotor and a series of vanes on an end wall secured'to sai flange and -ha'ving end ports .therein and la rotor havin venes extending toward said ports, carryingpart of anl end wall between adjoining vanes and utilizing the end wall on the flange for the remaining end Wall between .the vanes. 24. In a multistage pump, a. tor, op',

positel" directed varies' oni opposite facesl thereo some' on eachI 'face being arranged at. different "distances from the fcenter, in

combinationwith a stator, opposi'tely `di' rected cylindrical partitionscarried by the' V stator to cooperate with the rotor vanes and walls upon the stator forming .a' passage from `the outer surface of the outer partition of one part to the interior of the inner partition of the other. L.;

25. AIn amiiltistage ump, a stator, partitions thereon of Vcylin rical form in two sets extending 'toward each other, walls forming communication between the outside of one set and the inside ofr thel other, arotor mounted between the two sets-andoppositely 'facing vanes uponl the rotor cooperating with the two sets 'of partitions.

26. In a multistage vpump, a rotor,-blades l thereon in sets extending* away from each other axially on opposite sides of the rotor and some on each s xde at dill'erent distances from the axis,'in combination with a stator,

,partitions on the stator coperating with the rotor vanes to. 'form two axially-'staged fluid pumps and walls connecting the two pumps in series.

2?. In 'a multista e pump, an outer casing,

a stator structure t erein having a pluralitly of circular partitions ported at interva and arranged in two sets u on opposite llioth radially extendn in combination with a rotor. spider dividing the air on one side ofthe rotor from the air on the outer side thereof, Y

vanes on the .rotor extending axiall between the successiveu partitions and wa ls di. recting the fluid from the outside of' one Set' of partitions to the inside Vof the other set thereof.

THOMAS WL GREEN. 

